diff --git a/job/tf-merge-watcher/update_reference_repo.sh b/job/tf-merge-watcher/update_reference_repo.sh
index 65fff79..833ccf9 100755
--- a/job/tf-merge-watcher/update_reference_repo.sh
+++ b/job/tf-merge-watcher/update_reference_repo.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # Copyright (c) 2019, Arm Limited. All rights reserved.
 #